In the field of personal mobile devices such as laptop computers, tablet computers, and smart phones, proximity sensors are used to sense hover events. These are no touch, close proximity positioning of parts of the user's body or other objects (e.g., a stylus held by the user), near an external surface of the device. Typically, such proximity sensors are designed to detect an external object that is located outside the near field detection capability of a touch sensor (e.g., those used in a typical touch screen display such as found in an iPhone™ device by Apple Inc.). In one instance, the proximity sensor includes an infrared emitter and a counterpart infrared detector that are controlled and sampled by proximity sensor circuitry integrated in the housing of the mobile device. Emitted infrared radiation is scattered by the external object, and then detected and analyzed to infer that an external object is (or is not) close to the exterior surface. In the case of handheld mobile communications devices, the sensor may be located near an acoustic aperture for an earpiece speaker (receiver) of a mobile communications handset, and is used to determine when the handset is being held close to the user's ear, as opposed to away from the ear. When the proximity sensor indicates that the external object, in this case, the user's ear or head, is sufficiently close, then a predetermined action is taken, including, for example, turning off or disabling a touch screen display that is on the same external face of the housing as the acoustic aperture. This, of course, is designed to avoid unintended touch events caused by the user's cheek, while the handset is held close to the user's ear during a call.